(Business Statistics) Confidence interval question.

Hi everyone, can some1 kindly help me on these questions below. Thanks in advance!

Question 1.

A random sample of 49 people revealed that they listened to the radio and average (mean) of 40 minutes per day with a standard deviation of 14 minutes. Develop a 90% and 95% confidence interval for the population mean listening time.

1.Develop a 90% confidence interval for the population mean listening time.
2.Develop a 95% confidence interval for the population mean listening time.
3.Which of the two confidence intervals is wider?

Re: (Business Statistics) Confidence interval question.

Originally Posted by botakhenry

Hi everyone, can some1 kindly help me on these questions below. Thanks in advance!

Question 1.

A random sample of 49 people revealed that they listened to the radio and average (mean) of 40 minutes per day with a standard deviation of 14 minutes. Develop a 90% and 95% confidence interval for the population mean listening time.

1.Develop a 90% confidence interval for the population mean listening time.
2.Develop a 95% confidence interval for the population mean listening time.
3.Which of the two confidence intervals is wider?